JPS5818543B2 - Kanshiyoukinioker Gensuiriyokuhatsuseisouchi - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a damping force generating device in a shock absorber having a fluid sealed therein.

Some shock absorbers are designed to generate damping force by opening a so-called disk pulp using the pressure of a fluid corresponding to the piston speed.

This type of shock absorber is used as a shock absorber for automobiles to absorb vibrations and improve riding comfort.

Many of this type of shock absorbers are of the telescopic type, and the damping force characteristics on the expansion side and compression side are not the same, and the ratio is generally between 2=1 and 3:1.

Conventionally, in order to obtain a damping force frame with such a ratio, separate dispulps that act on the expansion side and disk pulps that act on the compression side are provided on both sides of the piston, and the characteristics of each disk pulp are determined based on this ratio. There are two types of disc pulp, one in which the damping force for both expansion and contraction is generated using a single disc pulp, and its characteristics are adjusted to match the above ratio.

The present invention relates to the latter, and the latter damping force generating device has a piston that defines two chambers in the fluid chamber attached to a piston rod that reciprocates within the fluid chamber, and the piston is attached to the piston rod from the axial direction. A disk pulp is inserted and supported, and the forward movement of the piston rod causes one of the outer circumference and inner circumference of the disk pulp to deflect, and the return movement of the piston rod causes the other to deflect, thereby opening the two chambers. In addition to the communication shear, the structure is such that a damping force is generated by the forward and backward movements of the piston rod, but when the inner diameter and outer diameter of the disc pulp are determined, the forward and backward movements of the piston rod are The damping force generated is determined, and the disadvantage is that it is difficult to appropriately change the damping force generated depending on the forward and backward movements of the piston rod.

The present invention has been made in view of the drawbacks of the above-mentioned prior art, and a feature of the present invention is that a second disc pulp formed separately from the disc pulp is attached to the piston rod from the axial direction of the piston rod. The second disc valve is deflected during one of the reciprocating movements of the piston rod, and the second disc valve is slid in the axial direction of the piston rod during the other reciprocating movement of the piston rod. It is installed in close contact with the disc valve so that the damping force generated by the piston rod's forward and backward movements can be changed as appropriate, and it is designed to minimize vibration when the disc valve opens and closes. be.

Embodiments of the damping force generating device for a shock absorber according to the present invention will be described below with reference to the drawings.

In FIG. 1, the inside of the pressure cylinder 4 of the shock absorber is divided into oil chambers A and H by a piston 5, which is an oil field defining member, and a piston rod 6 connected to the piston 5 is connected to the inside of the oil chamber A. It penetrates and extends to the outside of the pressure cylinder 4.

An outer cylinder 4' is provided on the periphery of the pressure cylinder 4 so as to be symmetrically positioned, and an oil chamber C is formed between the two cylinders 4 and 6, and a through hole 7 provided in the pressure cylinder connects the oil chamber C and the oil Communicate with room B.

Further, the upper part of the oil chamber C is an air chamber that absorbs the increase in volume ratio.

Both open ends of both cylinders 4.6 are closed with end plates 8A and 8B, respectively, and a fitting 9A for attaching to the vehicle body is attached to the end plate 8B.
A fitting 9B for attaching to the vehicle body is also attached to the end of the rod 6 that protrudes through the end plate 7A.

The piston 5 is equipped with a disc valve structure, and as shown in FIG. At the same time, the washer 11 fitted into the shaft 6 is supported by the flange 10A of the disc valve guide 10, and a washer 211 has a diameter smaller than that of the washer 11 on the back side. The bolt/nut 1 supports the valve retainer 12 which has been removed, further supports the piston 5 on its back surface, and is screwed onto the shaft portion 6A.
3, the disc valve guide 10, washer 11,
Valve retainer 12 and piston 5 are positioned and secured to the end of rod 6.

Then, there is 1 in the foot part 10B of the disc valve guide
The fitted first disc 1 (outer peripheral end 14a of loop 1.4)
The annular bearing surface 5B of the piston and piston 5 installed on the inner end surface of the oil chamber A.
and the inner peripheral end 1 of the disc valve 14.
4b is brought into contact with the back surface of the valve retainer 12.

In this state 5, the first disc valve 14 is subjected to an initial deflection load of 5 minutes.

A second disc valve 15 is provided at 5 so as to be slidable on the piston rod 6 and in close contact with the first disc valve 14 from the oil chamber A side, and its outer periphery is fitted into the leg portion 10B of the disc valve guide 10. , the inner peripheral surface 15a of the disc valve 15 is connected to the outer peripheral surface 12 of the valve retainer 12.
a.

Both the first and second disc valves 14,15 are annular, and there is a space 16 between the inner circumferential end 14b of the first disc valve 14 and the piston 5 through which fluid flows.
is constantly being formed.

Further, the annular seat surface 5B is provided with a permanent orifice 17 that communicates both oil chambers A and B, and the piston 5 is provided with an oil passage hole 18.

Next, the operation of the damping force generating device according to the present invention will be explained.

When the piston 5 is extended at a low speed, the oil in the oil chamber A first passes through the orifice 17 and generates a damping force of 6X as shown in FIG.

When it is further extended, the pressure of the oil in the oil chamber A increases,
The inner peripheral end 14b of the first disc valve 14 begins to bend and separates from the valve retainer 12, but at the beginning, the inner peripheral end 15' of the second disc valve 15 also bends.
As long as the inner peripheral surface 15a of the second disc valve 15 is in contact with the outer peripheral surface 12a of the valve retainer 12, no oil passage is formed between the valve retainer 12 and both disc valves 14 and 15. Not possible.

Furthermore, the pressure of the oil increases, and the first and second disc valves 14.45 are further deflected, and when the amount of deflection becomes equal to or greater than the plate thickness of the second disc valve 15, the disc valve 14 is closed. Oil between .15 and valve retainer 12,
A liquid passage is formed and this.

The flow resistance of the oil passing through the passage generates zero damping force as shown in FIG.

In this case, if the thickness of the second disc valve 15 is made thicker, a damping force of 10 CD can be obtained because the oil passage cannot be formed unless the disc valves 14 and 15 are bent more greatly.

In order to increase the thickness of the disc valve 15, instead of increasing the thickness of one disc valve, several disc valves 15 may be stacked one on top of the other to increase the thickness.

Furthermore, when acting on the compression side, the oil in the oil chamber B first flows into the oil chamber A through the orifice 17 and generates a damping force.

Then, when the speed of the piston 5 increases, the pressure in the oil chamber B increases, and the outer peripheral end of the first disc valve 14 is pinched, and the second
Along with this, the disc valve 15 of the piston rod 6
This first disc valve 14 slides in the axial direction of
The outer peripheral end of the piston 5 is spaced apart from the seat surface 5B, and a passage is formed between the piston 5 and the outer peripheral end of the first disc valve 14, and when the oil in the oil chamber B passes through this passage, a damping force is generated. Occur.

In this case, the second disc valve 15 does not function as a valve.

For this reason, a damping force that is smaller than the damping force on the extension side is generated.

In addition, in the implementation row (S), the second disk drive/1
Although the washer 11 is provided to prevent the second disc valve 15 from being removed, the diameter of the rod 6 may be made thicker (the rod 6 may be used instead to prevent the second disc valve 15 from being removed).

Further, the diameter of the second disc valve 15 may be smaller than the outer diameter of the first disc valve 14.

FIGS. 4 and 5 show other embodiments of the present invention,
In the embodiment in FIG. 1, the first disc valve 14
Although the outer diameter of the first disc valve 14 is fitted inside the disc valve guide 10 to regulate the 0 radial direction, in this embodiment, the rod 6 is To explain this with reference to a diagram in which the inner diameter of the first disc valve 14 is fitted to the outer diameter of the fitted annular disc valve guide 10' to restrict movement in the radial direction, as shown in Fig. 5. Projections 1σ' are provided at several locations on the outer periphery of the annular disc valve guide 10, positioned on the inner circle, and the disc valve guide 1σ is fixed to the rod 6 as shown in FIG.

Then, the protrusion 107 of the disc valve guide 11σ is fitted to the outside 5 of the first disc valve 14.

With the above configuration, the movement of the first disc valve 14 in the radial direction is restricted.

In FIG. 6, a spring 19 is interposed between the disc valve guide 10 and the second disc valve 15, and in order to prevent play by the spring 19, the second disc valve 15 is connected to the first disc valve. It is attached to the 14th side.

This product is particularly suitable for use in high frequency bands and for use in horizontal or vertical placement.

Furthermore, in each of the above embodiments, the inner peripheral ends of the disc valves 14 and 15 are bent in the expansion side operation, and the outer peripheral end of the disc valve 14 is bent in the compression side operation. Conversely, the outer peripheral end of the disc valve 14, 15 may be bent in the expansion side operation, and the inner peripheral end of the disc valve 14 may be bent in the compression side operation.

Since the present invention is constructed as described above, it has the following effects.

In other words, the second disc valve is deflected by one of the forward and backward movements of the piston rod,
In addition, since the second disc valve is provided on the piston rod so that the second disc valve slides in the axial direction of the piston rod when the other one moves,
By appropriately changing the plate thickness, number, spring constant, etc. of this second disc valve, the forward and backward movements of the piston rod can be prevented without changing the inner diameter and outer diameter of the first disc valve. The damping force can be changed as appropriate, and therefore the ratio of extensional and compressive damping forces can be adjusted as appropriate, and the two chambers defined by the piston are Even if the valve is deflected, these two chambers remain defined until the second disc valve is deflected and opened, so the two chambers are suddenly brought into communication by the deflection of the first disc valve. Therefore, the pressure fluctuations in these two chambers are alleviated, and it is possible to prevent the occurrence of natural vibration of the first disc valve.

[Brief explanation of drawings]

Fig. 1 is a sectional view of a shock absorber to which the device of the present invention is applied, Fig. 2, Fig. 4, and Fig. 6 are enlarged sectional views of essential parts showing one embodiment of the present invention device, and Fig. 3 is a damping device. The force characteristic diagram, FIG. 5, is an enlarged view of the disk valve 14 side. A, B... Oil chamber (2 chambers), 5... Piston, 6... Piston rod, 14...
...First disc valve (disc valve), 15.
...Second disc valve.

Claims (1)

[Scope of Claims] 1. A piston defining the fluid chamber into two chambers is attached to a piston rod that reciprocates within the fluid chamber, a disk pulp is inserted and supported through the piston rod from the axial direction, and the piston rod moves back and forth. Due to the movement, one of the outer circumference and inner circumference of the disk pulp is deflected, and the return movement of the piston rod causes the other to be deflected to communicate the two chambers, and the forward and return movement of the piston rod is also deflected. A damping force generating device for a shock absorber is configured to generate a damping force by moving a second disk pulp formed separately from the disk pulp onto the piston rod from the axial direction of the piston rod. During one of the reciprocating movements of the rod, the second disc pulp is deflected, and during the other reciprocating movement of the piston rod, the second disc pulp is deflected by the axis of the piston rod. A damping force generating device in a shock absorber, characterized in that the damping force generating device is provided in close contact with the disk pulp so as to slide in the direction.